[Braillenote] battery low

[John Gallagher]

Hi list how long after the message battery low do you have on the pk. I am 
trying to get my pk to go flat and then I hope I can connect the charger to 
get it working again. my charger came yesterday but no joy in starting it. 
it does get to the chime and then tahat's it but when on it switches off 
and says bat low just wondering how long to complete loss of power? thanks.